Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 1192-21-8, name is 1-Methyl-1H-pyrazol-5-amine, A new synthetic method of this compound is introduced below., COA of Formula: C4H7N3
3rd Generation BrettPhos precatalyst (31.1 mg, 0.03 mmol) was added to (iS)-2-(2-chloro- 5-methylpyrimidin-4-yl)-6-methyl-7-((4-(trifluoromethyl)pyridin-2-yl)mdihydroimidazo[l,2-a]pyrazin-8(5H)-one (Intermediate 80; 300 mg, 0.69 mmol), 1-methyl- lH-pyrazol-5-amine (167 mg, 1.72 mmol) and CS2CO3 (448 mg, 1.37 mmol) in 1,4- dioxane (8 mL) at 25°C under nitrogen. The resulting mixture was stirred at 100 °C for 8 hours. The solvent was then removed under reduced pressure. The crude product was purified by flash silica chromatography, elution gradient 0 to 6percent MeOH in DCM. Compound containing fractions were evaporated to dryness to afford a yellow residue. This residue was purified further by preparative HPLC (XSelect CSH Prep C18 OBD column, 5mu silica, 19 mm diameter, 150 mm length), using decreasingly polar mixtures of water (containing 0.03percent NH3) and MeCN as eluents. Fractions containing the desired compound were evaporated to dryness to afford (5)-6-methyl-2-(5-methyl-2-((l-methyl- lH-pyrazol-5-yl)amino)pyrimidin-4-yl)-7-((4-(trifluoromethyl)pyridin-2-yl)methyl)-6,7- dihydroimidazo[l,2-a]pyrazin-8(5H)-one (Example 28; 141 mg, 41.3percent) as a white solid. ^ NMR ^OO MHz, DMSO, 20 °C) delta 1.21 (3H, d), 2.52 (3H, s), 3.71 (3H, s), 4.13 (IH, dd), 4.37 (IH, dd), 4.52 (IH, dd), 4.58 (IH, d), 5.26 (IH, d), 6.31 (IH, d), 7.34 (IH, d), 7.71 (IH, d), 7.82 (IH, s), 7.95 (IH, s), 8.33 (IH, s), 8.84 (IH, d), 9.24 (IH, s). m/z (ES+), [M+H]+ = 498.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; ASTRAZENECA AB; WARD, Richard, Andrew; JONES, Clifford, David; SWALLOW, Steven; GRAHAM, Mark, Andrew; DOBSON, Andrew, Hornby; MCCABE, James, Francis; (223 pag.)WO2017/80979; (2017); A1;,
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